title: Early stage alopecia areata is associated with inflammation in the upper dermis and damage to the hair follicle infundibulum.
abstract: OBJECTIVE
  Alopecia areata (AA) is a non-scarring inflammatory hair loss disease. We investigated the early pathological changes of AA to identify possible factors participating in its pathogenesis.
  
  
  METHODS
  Clinical, laboratory and pathological features of 87 AA patients were investigated.
  
  
  RESULTS
  Anti-nuclear antibody was found in 11 of 85 patients tested (13%), with a higher percentage in women (21%) than men (5%) (P = 0.026). In early AA lesions, inflammatory infiltration in the upper dermis and epithelial cell damage of the hair follicle infundibulum, just above the sebaceous gland, was observed. Liquefaction and disarrangement of peripheral infundibular epithelial cells coexisted with T-lymphocytic invasion and regression of the lower follicle. The latter findings positively correlated with the presence of eosinophils and perivascular mononuclear cell infiltration in the upper dermis. Eosinophilic infiltration was found in 35 patients (40%) and was positively correlated to elevated serum IgE levels (r = 0.21, P = 0.044), a more severe perivascular lymphocytic inflammation in the upper dermis (r = 0.24, P = 0.026), as well as a prominent swarm of bees-like peri-follicular infiltration (r = 0.41, P < 0.001). Mast cells were abundant in the upper dermis, especially around blood vessels, and positively correlated with eosinophil presence (r = 0.30, P = 0.027).
  
  
  CONCLUSIONS
  Damage to the hair follicle infundibulum in the upper dermis might be an important component of early changes in AA lesions, possibly caused by lymphocyte cell infiltration in the same area. AA may involve damage of the upper hair follicle as well as the bulb, possibly involving hypersensitivity and autoimmunity.
authors.affiliation: Department of Dermatology, The First Affiliated Hospital, Sun Yat-sen University, 58 Zhongshan Road II, Guangzhou, Guangdong, China.
authors.forename: Bin
authors.initials: B
authors.lastname: Zhang
authors.forename: Ying
authors.initials: Y
authors.lastname: Zhao
authors.forename: Zeming
authors.initials: Z
authors.lastname: Cai
authors.forename: Sillani
authors.initials: S
authors.lastname: Caulloo
authors.forename: Kevin J
authors.initials: KJ
authors.lastname: McElwee
authors.forename: Yang
authors.initials: Y
authors.lastname: Li
authors.forename: Xiaohong
authors.initials: X
authors.lastname: Chen
authors.forename: Mei
authors.initials: M
authors.lastname: Yu
authors.forename: Jian
authors.initials: J
authors.lastname: Yang
authors.forename: Wenna
authors.initials: W
authors.lastname: Chen
authors.forename: Xuhua
authors.initials: X
authors.lastname: Tang
authors.forename: Xingqi
authors.initials: X
authors.lastname: Zhang
mesh_terms: D000293:Adolescent; D000328:Adult; D000506:Alopecia Areata / Q000150:complications / Q000276:immunology / Q000473:pathology*; D000974:Antibodies, Antinuclear / Q000097:blood; D002648:Child; D003872:Dermatitis / Q000150:complications / Q000473:pathology*; D004804:Eosinophils; D005260:Female; D018859:Hair Follicle / Q000473:pathology*; D006801:Humans; D007073:Immunoglobulin E / Q000097:blood; D008214:Lymphocytes; D008297:Male; D008407:Mast Cells; D008875:Middle Aged; D012737:Sex Factors; D055815:Young Adult
chemical_list: D000974:Antibodies, Antinuclear; D007073:Immunoglobulin E
keywords: alopecia areata; cutaneous inflammation; damage of hair follicle; eosinophil; mast cell